1. Field of the Invention
The present invention relates generally to devices and methods for tagging industrial, architectural, and machine structures and components. The present invention relates more specifically to a method and apparatus for the tagging of industrial, architectural, and machine components within harsh environments and the detection and reading of information contained on the tag.
2. Description of the Related Art
The installation, maintenance and upgrade of industrial, engineering, and architectural fixtures, machines, components and so on, relies to a great extent on accurate inventories and records on each specific element within the systems. Many of the components within industrial and architectural systems have specific life spans and require monitoring and/or replacement at regular intervals. Safety requirements, environmental concerns, and many government regulations require that industries maintain accurate logs on many of the structural and functional components of the physical plants with which the industry operates.
The typical method for maintaining these inventories and records involves the visual inspection of components by an inspector on a periodic basis. These inspections can take the form of simple written logs on pieces of paper that identify specific components and their condition. In order to consistently identify these components, it is typical to tag the devices or objects with descriptive or symbolic codes that can be consistently referred to as repeat inspections are made.
In use today are tags of many different designs; all with limitations in size, shape, and the amount of information contained on the tag. They are attached commonly with rivets, or screws and are made of many different types of materials. Standardization of tag structures of any kind is limited to the very basic information needed for the type of equipment. The life expectancy of these types of tags and the means for attachment are in many cases very limited due to shock, vibration, weather exposure, sandblasting, paint overspray and process hazards.
Commonly, industrial equipment tags used in harsh environments are of two basic types. They are made of sheet metal material and incorporate either raised letters or engraved letters for retaining the identification information. Both types are normally stencilled or electroplated with paint to show generic information descriptive of the type of equipment, with the specific design information engraved or pressed in raised lettering. These types of tags are very common and can be seen on motors, pumps, turbines, pressure vessels, etc.
Still, another type of tag existing today is the bar code tag. This tag is a sticker with bar code information on one side and is attached like tape to a metal tag or directly to the piece of equipment. These types of tags have even a shorter life span than the former types discussed above.
The tags discussed above all hold information such as model, serial number, horsepower, voltage, flow capacity, rpm values, maximum working pressures and temperatures, etc. The information on these tags is vital for on site inspection by operators, maintenance personnel, and inspectors.
Currently tags do not exist that can withstand the harsh environment they are frequently exposed to in the process industry. The information on such tags has become increasingly important because of current process industry regulations. As an example, OSHA 1910.119 and other OSHA regulations relating to inspection and testing, require the testing of process equipment and the documentation of such test results. This will ultimately require being able to identify the piece of equipment through its serial number, and then for proper testing, the limits of the equipment and other pertinent information.
One method developed in recent years utilizes ultrasound echoing techniques for the identification of valuable art and has a unique data encrypted tag. U.S. Pat. No. 4,749,847, issued to Jean-Albert Despres on Jun. 7, 1988, describes a method and device for identifying a valuable object. This method and apparatus is not well suited for the harsh environments of the process industry and would be a very costly design if implemented on a large scale. The cost associated with the cutting of curvalinear notches and its basic design features make it impractical.
The method for reading the tag described in the Depres patent is too time consuming and therefore not cost effective. The ability of a technician to read a tag continuously and rapidly is of paramount importance. It would be desirable to design a tag capable of being read by a transducer in a sweeping motion across its face. In addition, there is a need for an attachment mechanism that will allow longevity, and a cost effective means for manufacture of massive quantities. Inherently, the tag must be equipped to withstand cyclic temperatures, vibrations, shocks, weather, chemical attack, sandblasting, paint overspray, abuse from turnover, light exposure, pressure and so on.